This invention relates to a method for mass production of interferon which comprises contacting cultured cells with polyhydric alcohol.
Interferon was discovered by Nagano et al. (Compt. Rend. Soc. Biol., Vol. 148, p. 1700, 1954) and Isaacs et al., (Proc. Roy. Soc. Ser. B, Vol. 147, p. 258, 1957). Recently, it has been reported that interferon has various biological activities such as anti-tumor effects (Gressor et al., B. B. A., Vol. 516, p. 231, 1978), in addition to anti-viral activity, and attention has been given to its possible use as a therapeutic agent. Interferon is classified roughly into 3 groups. These groups are named interferon-.alpha., interferon-.beta., and interferon-.gamma. (Nature, Vol. 286, p. 110, 1980).
Interferon-.alpha. is induced by stimulating cultured leukocytes or lymphoblastoid cells with various viruses such as Sendai virus (HVJ), Newcastle disease virus (NDV), and influenza virus.
Interferon-.beta. is induced by stimulating normal diploid cells with various viruses such as HVJ, NDV, and influenza virus, or with double-stranded RNA, etc. This method has been improved markedly in recent days. For example, the superinduction method by Vilcek, et al. (Antimicrob. Ag. Chemother., Vol. 2, p. 476, 1972), which comprises stimulating the cells with inducers such as double-stranded RNA and thereafter treating them with metabolic inhibitors such as cycloheximide and actinomycin D, remarkably enhances the production of interferon-.beta..
Interferon-.gamma. is induced by stimulating T lymphocytes with mitogens such as phytohemagglutinin (PHA) and concanavalin A (Con A) or with antigen-antibody reactions.
It is also known that the production of interferon is enhanced by overnight incubation of cells in a medium containing interferon prior to stimulation with the various inducers. This is the so-called priming effect.